In 2025, agents don’t just think — they run code, call tools, and complete tasks.
This Build Hour is a hands-on walkthrough of how to design agentic systems that reason and act using OpenAI’s latest APIs and SDKs.
Ilan Bigio (Developer Experience) covers: - What’s new in 2025: Responses API, Agents SDK, Hosted Tools, Codex, and more - Chain of thought concepts: reasoning, tool calling, and long-horizon tasks - Live demo: building an agentic task system to process a backlog of tickets - Delegation: directional guidance for evals - Live Q&A
👉 Follow along with the code repo: https://github.com/openai/build-hours 👉 Check out additional resources: https://developers.openai.com/ 👉 Sign up for upcoming live Build Hours: https://webinar.openai.com/buildhours
